"WASHINGTON — Gregory B. Jaczko, whose three-year tenure as chairman of the Nuclear Regulatory Commission has been marked by bitter battles with colleagues and with Congress, announced Monday that he would step down as soon as a successor was confirmed."

"Dr. Jaczko, chairman since May 2009 and the longest-serving member of the five-member commission, was an outsider and a maverick. He had drawn sharp criticism for helping to end government consideration of a proposed nuclear waste dump at Yucca Mountain, a volcanic ridge about 100 miles from Las Vegas, and for assuming some emergency powers at the commission after the triple meltdown of Japan’s Fukushima Daiichi reactors in March 2011.

He sought to address some longstanding safety problems at America’s nuclear power reactors, but with a background in nuclear physics and nuclear policy but not the nuclear industry, Dr. Jaczko was long viewed with skepticism and mistrust by some industry insiders.

In a telephone interview Sunday, Dr. Jaczko refused to talk about his clashes with other commissioners, which resulted in an internal commission investigation and Congressional hearings."